VERTEBRAL ENDPLATE CHANGES: THE NATURAL HISTORY AS ASSESSED BY CONSECUTIVE MAGNETIC RESONANCE IMAGING.

Abstract

Study Design: Retrospective review of 55 subjects who for various clinical indications had sequential MRI scans

Summary of Background data: Changes in the vertebral end plate are frequently associated with degenerative disc disease. These are called Modic changes. The changes were first classified into two types. Type I changes include decreased signal intensity on T1-weighted and increased signal intensity on T2-weighted images. In type II, signal intensity is increased in both T1- and T2-weighted sequences. Type I changes are assumed to be a result of fibrovascular replacement of subchondral bone and type II changes are the manifestation of fatty replacement of subchondral bone and are considered to be chronic. These changes can be separated only on magnetic resonance imaging (MRI). If bone sclerosis is extensive, signal intensities are decreased in both T1- and T2- weighted images, and this change in the end plate is called type III change. It is again assumed that these endplate changes represent a process that is progressive (Type I converts to Type II converts to Type III). To our knowledge there is little evidence to support such assumptions.

Objective: To investigate the hypothesis that Modic changes are a progressive degenerative process.

Subjects: The average time interval between MRI scans was two years. No subjects had had surgical intervention. The lumbar vertebral endplates were classified using the Modic system and the results compiled to provide further data on the natural history of these endplate changes.

Results: Of the endplates that had Modic type I changes on the first MRI scan, 6% had reverted to a normal MRI endplate appearance on subsequent scan. Of those with Modic type II appearance 18% were normal or type I on subsequent scan.

Conclusions: This data would not support the hypothesis that Modic changes observed on MRI are a progressive degenerative process.